Effects of Curing Time Using Crushed Coconut Shell (CCS) and Coconut Shell Ash (CSA) as Additive to Improve Lateritic Soils

Abstract

Numerous constructions in Malaysia have encountered the issues where soil cannot fulfil the standard required specification due to the bearing capacity of soft soil is too weak to withstand traffic loading. Recently, there is a lot of defeats related to soil settlement and distorting of the structure effect by the inflated compressibility and low in shear strength of the soil. This research study on the effects of natural additives in crushed coconut shell (CCS) and coconut shell ash (CSA) to enhance the durability of lateritic soil for road pavement. The effects of curing time in the CCS and CSA admixture of soil is examined. Different proportions of 5% and 9% CSA with a constant 8% CCS were used to study the effect on lateritic soil. Series of preliminary tests were performed followed by engineering test of Compaction test in identification on optimum moisture content (OMC) and maximum dry density (MDD) followed by California Bearing Ratio (CBR) for curing day of 4 days, 7 days and 14 days of soil mixtures sample to investigate its enhancement to soil strength. Further review from the previous research has also been carried out and it is pointed out that by using natural CCS and CSA brushed up the soil load-bearing capacity due to the increment of CBR value obtained as compared to the normal mix. Hence, it can be concluded that the combination of natural additives CCS and CSA in the soil also have the capability to improve the soil strength and can be suggest to replace aggregates and cement for use in lateritic soil stabilization subject to road works.